Question

What will be the least number which when doubled will be exactly divisible by $12$, $18$, $21$ and $30$?

• A. $196$
• B. $630$
• C. $1260$
• D. $2520$

Answer 1

Answer: (B)

$630$

L.C.M. of $12$, $18$, $21$, $30$
$=2\times 3\times 2\times 3\times 7\times 5=1260$.
Required number $=(1260÷2)$
$=630$.